I think many non-developers would agree that if you can't leave Pandora playing music while you go check your email, you don't have multi-tasking.

Even more significant to me (and some large competing industries): can you receive a VOIP call while using another app?

Skype on the iPhone/iPad is great, except for the need to pre-arrange simultaneous launch.

Skype could use push notifications for incoming calls just fine.

Are they fast and reliable enough? (My understanding was that part of the Urban Airship value proposition was helping to paper-over the unreliability of Apple's push notifications.)

You absolutely do not need multi-tasking (for 3rd party apps) to have background music. You simply need to expose the system media player as a service. I'd actually much prefer that solution. In fact, _most_ backgrounding needs would be better as a sensible system service call. Services could be provided for scheduling jobs, callbacks for location awareness events, etc.

Which is pretty much the way Android currently does it. http://developer.android.com/guide/topics/fundamentals.html#...

Yeah, you're right. Streams are tricky- music and network too. I think Android solves it using services; would be interesting if Apple comes up with something different (I don't like daemons on my phone personally; but maybe it doesn't matter to most people.)

Sorry I accidentally downvoted you. I agree with you. From a consumer point of view not being able to play music in the background makes the iPhone OS seem incomplete.

To be clear, you can have music playing in the background, but only from Apple's iPod app, not from 3rd-party apps like Pandora.

I think it's also possible to play a background stream in Safari.

Those non-developers apparently never used DOS or other non multi-tasking OSs.

What do you mean non-developers. Developers too.

I wonder if some sort of hybrid of the current push notifications and GCD might prove a workable stopgap? I.e., apps can register asynchronous event listeners while running, and push notifications can trigger those to give the appearance of multitasking.

If the background listeners/workers are heavily resource-constrained and subjected to limited API access, you might be able to maintain most of the battery life and performance advantages of the current single-task model, while still allowing apps to perform some amount of background processing. Any "heavy lifting" involving a full app UI, the GPU, or outbound network access could still require user confirmation and a task swtich.

Sounds a lot like how background workers are handled in Android. http://developer.android.com/guide/topics/fundamentals.html#...

It's funny, because when I heard the original description of the iPhone push notifications at WWDC, that's exactly how I thought it worked.

That'd be a fairly good compromise.

I just released an app that uses a timer for a main feature of the application. The first (and so far only) user e-mail I received was this:

"Is there a way to shut off the iPod Touch while the countdown timer is working and the iPod Touch will wake up when the alarm goes off"

What's to agree on? You either have multiple, concurrent tasks or you do not.

To a consumer, having interleaved tasks might appear like multi-tasking while it technically isn't (which you point out).

False dichotomy.

You clearly have the ability to receive phonecalls at all times, so the phone is running so you have multiple concurrent tasks so there's no argument.

Except there is an argument, so that isn't what's really being discussed even if the discussion is framed by that term.

I'm sorry but there isn't a false dichotomy between multi- vs. single-tasking, or did you mean to imply something else? I know the operating system is a multitasking environment, but that aspect of it is not exposed in any kind of useful way outside of Apple's pre-chosen features.

As a technical description maybe there isn't, but at user level there is; one or the other or somewhere in between. This is what people are arguing about that you unhelpfully dismissed.

I guess the disagreement is about whether multiple, concurrent tasks are necessary or not.

I think most people are used to their computers being able to play music and browse the Web at the same time. If Apple wants to push the iPad as a computing device, they might hit a snag with consumers.

Edit: Whoops. I'll leave the comment but I do realize this isn't an iPad thread.

In any case, you can browse and use the iPod app at the same time.